identifyMissing: A checkFunction for identifying miscoded missing values.
In dataReporter: Reproducible Data Screening Checks and Report of Possible Errors

Description Usage Arguments Details Value See Also Examples

A checkFunction to be called from check that identifies values that appear to be miscoded missing values.

1	identifyMissing(v, nMax = 10, ...)

`v`	A variable to check.
`nMax`	The maximum number of problematic values to report. Default is `10`. Set to `Inf` if all problematic values are to be included in the outputted message, or to `0` for no output.
`...`	Not in use.

identifyMissing tries to identify common choices of missing values outside of the R standard (NA). These include special words (NaN and Inf (no matter the cases)), one or more -9/9's (e.g. 999, "99", -9, "-99"), one ore more -8/8's (e.g. -8, 888, -8888), Stata style missing values (commencing with ".") and other character strings ("", " ", "-", "NA" miscoded as character). If the variable is numeric/integer or a character/factor variable consisting only of numbers and with more than 11 different values, the numeric miscoded missing values (999, 888, -99, -8 etc.) are only recognized as miscoded missing if they are maximum or minimum, respectively, and the distance between the second largest/smallest value and this maximum/minimum value is greater than one.

A checkResult with three entires: $problem (a logical indicating whether midcoded missing values where found), $message (a message describing which values in v were suspected to be miscoded missing values), and $problemValues (the problematic values in their original format). Note that Only unique problematic values are listed and that they are presented in alphabetical order.

check, allCheckFunctions, checkFunction, checkResult

#Identify miscoded numeric missing values
v1 <- c(1:15, 99)
v2 <- c(v1, 98)
v3 <- c(-999, v2, 9999)
identifyMissing(v1)
identifyMissing(v2)
identifyMissing(v3)
identifyMissing(factor(v3))